The present invention relates to ventilators such as glazed-in or slot ventilators for use at windows or doors where it is desirable to provide ventilation without having to open the window or door.
This application is the National Stage of International Application No. PCT/GB98/02249, filed Jul. 28, 1998, which claims priority to UK Patent Application No. 9716000.6, filed Jul. 29 1997.
A known slot ventilator is described in GB11417751.
A known glazed-in ventilator is described in GB-A-2224826. The ventilator comprises a body which is adapted to be located adjacent a window at a ventilation path between two sides of the window. The ventilator has a body or housing which is adapted to be located in a gap left between the top edge of a pane of glass and a peripheral spar of a window frame, usually the upper spar of a rectangular frame. An upper edge of the housing has substantially the same thickness as the panel of glazing itself and the ventilator fills the substantially rectangular gap between the panel of glazing and the upper spar of the frame which may be a sash frame.
This ventilator and the slot ventilator referred to above perform well in many applications, but in some circumstances it is possible for exterior debris, such as dust, to be carried through these ventilators into the room which they serve.
The present invention aims to alleviate the problems of the prior art.
According to a first aspect of the present invention there is provided a ventilator comprising a body or housing which is adapted to be located adjacent a window or door at a ventilation path between two sides of the window or door, the body including a filter for filtering air passing through the ventilator. The ventilator is therefore advantageously able to provide ventilation of substantially cleaner air to a room since debris such as dust will be caught by the filter. Preferably the filter is removable from the body, preferably once the body is in situ in a window or door assembly.
Preferably, the body includes a chamber containing the filter, and at least part of the chamber is defined by a removable cover portion of the body, the filter being removable from the body once the cover has been removed or on removal of the cover portion. This enables the filter easily to be cleaned or replaced when servicing is desirable. This construction is considered to be particularly inventive. Previously, slot ventilators or glazed-in ventilators have been located as permanent fixtures in window or door assemblies and the incorporation of a cover portion and/or filter which may be removed from the body while the ventilator is in situ at a window or door assembly is considereda considerable advance.
According to a further aspect of the invention there is provided a ventilator comprising a body or housing which is adapted to be located adjacent a window or door at a ventilation path between two sides of the window or door, the body including a chamber which is adapted to contain a filter for filtering air passing through the ventilation path. Preferably, the chamber contains a filter, and at least part of the chamber is defined by a removable cover portion of the body or housing, the filter being removable from the body or housing on removal of the cover portion or once the cover portion has been removed. The advantages of this structure will be apparent from the above text, notably that the filter may be easily removed from the ventilator, while the ventilator is in situ, for servicing by cleaning or replacing the filter.
According to another aspect of the invention a ventilator (such as for use at a window door or wall) comprises a body and a filter in the region of the body for filtering air passing through the body.
A number of preferred features which are applicable to each of the above mentioned aspects of the invention will now be discussed.
Preferably, where the ventilator includes a said chamber with a said cover portion, the chamber is partly defined by an apertured wall portion of the body, the cover portion being removably mounted to the apertured wall portion, the ventilator being adapted to be mounted in a window or door assembly with the cover portion on an interior side of the window or door. Therefore, the cover portion and filter may conveniently be removed from the rest of the ventilator by a person on the inside of the window or door.
The body or housing may include a closure for controlling the level of ventilation through the ventilator. In this case, the closure may comprise a flap which is pivotally coupled to the apertured wall portion on one side thereof, the filter and cover portion being located on an opposite side thereof.
The ventilator may comprise a glazed-in ventilator for a window assembly, the ventilator being adapted to be located at an elongate rectangular gap between a pane of glazing and a peripheral spar of a window. Preferably, the body or housing is elongate. The body may include a weather hood and the ventilator may be adapted to be mounted at a window or door assembly with the weather hood on an exterior side of the window or door. The weather hood, apertured wall portion and cover portion of the housing, where such are provided, may each be formed as elongate extrusions. The ventilator may include an end cap at one or each end of the housing or body for securing parts of the body, e.g. the apertured wall portion and weather hood together. The end cap may include an end wall portion for forming an end wall of the chamber, partly defined by the cover portion, where such are provided.
When a filter is provided, it preferably comprises a reticulated foam filter. The filter may be provided as a brick or blocklike element of material.
The filter is preferably a foam filter which is substantially fully open celled, preferably at least 90% to 100% of the cells by number being opened. The foam may be a polyurethane foam.
The porosity of the foam of the filter, when it is a foam filter, may be between 7 and 100 pores per inch, one example having between 7 and 15 pores per inch and another about 10 pores per inch. A straight line through the foam may, on average, pass through between 7 and 100 pores per inch, e.g. 7 to 15 pores per inch or about 10 pores per inch. Therefore, the foam is relatively porous to air flow and does not substantially restrict mass flow rate through the ventilator. The average diameter of pores or cells in the foam filter may be about half to 5 mm, or 1 to 3 or 1 to 2 mm in diameter. The foam filter is preferably an unskinned foam.
The foam of the filter preferably has a density of about 20 to 40 kg per cubic metre, about 26 to 32 kg per cubic metre being employed in some applications.
When the filter is a reticulated foam, it is envisaged that the volume of foam ribs of the foam filter may be 1 to 10% or 2 to 5% and preferably about 3% of the overall volume of the foam filter.
The above discussed parameters of the foam filter may be contrasted with those of typical acoustic foams which are significantly denser or less porous, being more restrictive of air flow. However, the ventilator may incorporate acoustic foam, if desired, for improving the acoustic characteristics thereof.
In a preferred embodiment, the chamber is elongate and of substantially rectangular cross section, and the cover portion incorporates at least one ventilation aperture, preferably a series of ventilation apertures passing therethrough, e.g. for allowing air to pass into the interior of a space, e.g. a room or other interior space which the ventilator is adapted to service, and vice versa. In this case, the aperture or series of apertures are preferably on one side of the chamber and the apertured wall portion has at least one aperture, preferably a series of apertures spaced along the ventilator, on an opposite side of the chamber. In this case, the foam filter may be located between the aperture or apertures of the apertured wall portion and the aperture or apertures of the cover portion to filter air passing between these apertures. In this case, the thickness of the foam across the chamber from the aperture or apertures in the apertured wall portion to the aperture or apertures in the cover portion is preferably at least 10 mm, 15 to 30 mm being envisaged as typical, the value being 16 mm in one embodiment and 17 mm in another.
Preferably, the foam filter has porosity to air flow such that, at pressure differentials across the ventilator of less than or equal to 30 Pa, with the ventilation path fully blocked by a 17 mm thick section of the foam, the mass flow rate of air through the ventilator at standard atmospheric conditions is at least 60% of the mass flow rate through the ventilator that would result if the foam filter were removed and the ventilator was otherwise unchanged.
Where the ventilator includes an apertured wall portion and a flap pivotally mounted thereon, the ventilator preferably has snib means for operating the flap. Preferably, the ventilator is adapted to be located with the flap on an exterior side of the apertured wall portion and with the snib means providing a linkage to a manually operable snib to the interior side of the apertured wall portion and/or the ventilator or window or door assembly to which it may be mounted. The snib means may include one or more detents for locking the flap in a selected angular orientation relative to the apertured wall portion. The flap may be pivotally mounted at an upper edge thereof to the apertured wall portion and may include a seal at a lower edge thereof.
Another aspect of the invention provides a window or door assembly having a ventilator as set out in any of the above mentioned aspects of the invention mounted therein for providing ventilation from one side of the assembly to the other.
The assembly may comprise a window assembly having a first pane of window glazing which is surrounded by a peripheral sash frame the ventilator being a glazed-in ventilator which is located between an edge of the pane of window glazing and the peripheral sash frame. The assembly may include a second pane of window glazing which is surrounded by a second peripheral sash frame, the first and second peripheral sash frames being located inside a fixed frame, the first and second sash frames being planar, mutually parallel and offset from one another. Preferably, at least one of the sash frames is slidable in the sash frame to an open configuration of the window assembly. When the window assembly is located in situ on a building structure such as a wall of a space such as a room, the first sash frame may be located to the interior of the second sash frame and the ventilator may project in an exterior direction no further than the first sash frame (i.e. the ventilator is flush or sub-flush). In this case, at least one of the sash frames may be slidable in the fixed frame to an open configuration of the window assembly in which the ventilator is at least partly overlapped, when viewed in a direction orthogonal to the sash frames, with the second pane of window glazing. This structure, in which the ventilator has zero exterior projection therefore allows convenient sliding opening of the window assembly. If the ventilator were to project sufficiently to the exterior, it might adversely prevent or jam such sliding movement.